The present invention relates broadly to apparatus for controlling the disposition of knitted, tubular fabric being removed from a circular knitting machine. More particularly, the present invention is directed to an apparatus for controlling twist in a tubular knitted fabric as it is being withdrawn from a circular knitting machine.
Circular knitting is often employed to produce jersey fabric rapidly for use in polo shirts, underwear, and other similar jersey apparel. Within a circular knitting machine, a multiplicity of needles arranged in a circular pattern around the perimeter of a hollow cylinder are fed from an array of yarn packages. The cylinder rotates and the needles are typically cam driven in a predetermined pattern for knitting. The resultant fabric is a knitted, tubular construction and is withdrawn from under the needle cylinder and wound on a rotating mandrel. The mandrel typically rotates about its own longitudinal axis to wind the fabric and it rotates about a vertical axis coincident with the axis of rotation of the needle cylinder to prevent the fabric from twisting into a knotted rope as it is withdrawn from the needle cylinder.
Due to the traverse distance between the wind-up mandrel and the fabric emission portion of the needle cylinder, the knitted fabric can develop a slight twist which has detrimental effects on the finished product. As the tubular fabric is rolled onto the mandrel, creases are inherently formed at the selveges defined by the roll. It would be ideal if the selveges were parallel with the wale of the fabric. However, due to the twist, the wale of the fabric can cross over the selvege, resulting in fabric which is difficult to work. If the net resultant wale of the fabric is out of alignment with the selvege, it becomes more difficult to align sleeves and legs in garments and causes problems with dyeing and other finishing operations.
Therefore, a need exists to control twist of tubular knitted fabric as it is being withdrawn from a circular knitting machine.